1. Field
The present disclosure relates generally to communication systems, and more particularly, to a differential mode bandwidth extension technique with common mode compensation.
2. Background
A wireless device (e.g., a cellular phone or a smartphone) may transmit and receive data for two-way communication with a wireless communication system. The wireless device may include a transmitter for data transmission and a receiver for data reception. For data transmission, the transmitter may modulate a transmit local oscillator (LO) signal with data to obtain a modulated radio frequency (RF) signal, amplify the modulated RF signal to obtain an output RF signal having the desired output power level, and transmit the output RF signal via an antenna to a base station. Additionally, the transmitter may include a digital-to-analog converter (DAC), which may be coupled to a transconductance (gm) circuit. The DAC may assist in the generation of the output RF signal that is transmitted.
A DAC converts digital signals (e.g., a 4-bit DAC converts a digital word of four bits, such as a digital signal of 0110) into a corresponding current or a corresponding analog voltage. A four-bit DAC will produce a different analog voltage value, or a different amount of current, for each possible digital value. That is, the four-bit DAC will produce a different current or analog voltage for each value of the digital signal from 0000 to 1111.